package com.itheima.test;

import com.itheima.domain.Student;

import java.util.ArrayList;
import java.util.Scanner;

public class StudentManager {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        ArrayList<Student> list = new ArrayList<>();
        lo:
        while (true) {
            System.out.println("--------欢迎来到学生管理系统--------");
            System.out.println("1 添加学生");
            System.out.println("2 删除学生");
            System.out.println("3 修改学生");
            System.out.println("4 查看学生");
            System.out.println("5 退出");
            System.out.println("请输入您的选择:");
            String choice = sc.next();
            switch (choice) {
                case "1":
                    addStudent(list);
                    break;
                case "2":
                    delStudent(list);
                    break;
                case "3":
                    updateStudent(list);
                    break;
                case "4":
                    queryStudent(list);
                    break;
                case "5":
                    System.out.println("感谢您的使用!");
                    break lo;
                default:
                    System.out.println("您输入的有误~");
                    break;
            }
        }
    }
    //修改学生信息
    private static void updateStudent(ArrayList<Student> list) {
        Scanner sc = new Scanner(System.in);
        String updatesid="";
        int index = 0;
        while (true){
            System.out.println("请输入要修改的学号:");
            updatesid = sc.next();
            index = getIndex(list, updatesid);
            if(index==-1){
                System.out.println("您要修改的学生不存在,请重新输入");
            }else{
                break;
            }
        }
            System.out.println("请输入修改的姓名:");
            String name = sc.next();
            System.out.println("请输入修改的年龄:");
            int age = sc.nextInt();
            System.out.println("请输入修改的生日:");
            String birthday = sc.next();
            Student s = new Student(updatesid,name,age,birthday);
            list.set(index,s);
            System.out.println("修改成功");

    }

    //查看学生信息
    public static void queryStudent(ArrayList<Student> list) {
        if(list.size()==0){
            System.out.println("无信息,请先添加后再查看!");
            return;
        }
        System.out.println("学号\t\t姓名\t\t年龄\t\t生日");
        for (int i = 0; i < list.size(); i++) {
            Student stu = list.get(i);
            System.out.println(stu.getSid()+"\t"+stu.getName()+"\t\t"+stu.getAge()+"\t\t"+stu.getBirthday());
        }
    }
    //删除学生信息
    public static void delStudent(ArrayList<Student> list) {
        Scanner sc = new Scanner(System.in);
        System.out.println("请输入要删除的学号:");
        String delsid = sc.next();
        int index = getIndex(list, delsid);
        if(index==-1){
            System.out.println("您要删的学生不存在,请重新输入");
        }else{
            list.remove(index);
            System.out.println("删除成功!");
        }
    }
    //添加学生信息
    public static void addStudent(ArrayList<Student> list) {
        Scanner sc = new Scanner(System.in);
        String sid;
        while (true){
            System.out.println("请输入学号:");
            sid = sc.next();
            int index = getIndex(list, sid);
            if(index !=-1){
                System.out.println("您输入的学号已存在!请重新输入!");
            }else{
                break;
            }

        }

        System.out.println("请输入姓名:");
        String name = sc.next();
        System.out.println("请输入年龄:");
        int age = sc.nextInt();
        System.out.println("请输入生日:");
        String birthday = sc.next();
        Student stu = new Student(sid,name,age,birthday);
        list.add(stu);
        System.out.println("添加成功!");
    }
    //判断学号是否存在
    public static int getIndex(ArrayList<Student> list,String sid){
        int index = -1;
        for (int i = 0; i < list.size(); i++) {
            Student stu = list.get(i);
            String s = stu.getSid();
            if(s.equals(sid)){
                index = i;
            }
        }
        return index;
    }
}
